Washington County is a county in the U.S. state of Idaho. As of the 2010 census, the population was 10,198. The county seat and largest city is Weiser, with over half of the county's population. The county was established in 1879 when Idaho was a territory and named after U.S. president George Washington.
Equine Gestation. Miniature ponies, and all other breeds of horses, typically carry their foals for approximately 11 months. The average miniature horse mare will carry her foal for around 330 days before giving birth. The actual length of pregnancy can vary between 320 days and 380 days.
It may seem like waiting for the birth of a foal takes an eternity, but the average gestation length for most mares is 335 to 340 days (range 320 to 350 days).